Snap mechanism for use in electrical switches, fluidic switches, valves, etc.

ABSTRACT

This invention deals with a push-push snap mechanism in an electrical switch, in a valve and other applications snap mechanism consisting of a stem and a resilient cup, with two related positions. The stem carries the moving contacts, which are bridging stationary contacts. The junction lines of stem with bottom of cup and of bottom of cup with walls of cup are undercut and form hinges. The valve stem carries flexible lips which seal the valve preventing fluid leakage, and also seals the valve ports until the snap occurs (when so programmed).

United States Patent 1 Raitport July 31, 1973 [5 SNAP MECHANISM FOR USEIN 3,264,884 8/1966 Brooker 267/159 x ELECTRICAL SWITCHES, FLUID:3,609,266 9/1971 Raitport 200/ 159 B 3,582,594 6/1971 Twyford 267/ 159 XSWITCHES, VALVES, ETC.

Eli Raitport, 1807 Mower St., Philadelphia, Pa. 19152 Filed: Apr. 5,1971 Appl. N0.: 130,939

Related U.S. Application Data Continuation-impart of Ser. No. 821,547,April 18, 1969, Pat. No. 3,609,266.

Inventor:

References Cited UNITED STATES PATENTS 9/1953 Engstrum 251/75 PrimaryExaminer-Henry T. Klinksiek [57] ABSTRACT This invention deals with apush-push snap mechanism in an electrical switch, in a valve and otherapplications snap mechanism consisting of a stem and a resilient cup,with two related positions. The stem carries the moving contacts, whichare bridging stationary contacts. The junction lines of stem with bottomof cup and of bottom of cup with walls of cup are undercut and formhinges. The valve stem carries flexible lips which seal the valvepreventing fluid leakage, and also seals the valve ports until the'snapoccurs (when so programmed).

12 Claims, 21 Drawing Figures A PATENTHJ 3. 749 354 SHEET 1 BF 4INVENTOR:

PATENIED JUL 31 I975 SHEET 4 [IF 4 IIIIIIIIVIAIIII 7/ III//IIIIIIIIIIIIII I68 INVENTOR SNAP MECHANISM FOR USE IN ELECTRICALSWITCHES, FLUIDIC SWITCHES, VALVES, ETC.

This application is a continuation in part of application, Ser. No.82l,547, filed Apr. I8, I96), now U.S. Pat. No. 3,609,266.

The purpose of these improvements is to provide full proofness for thedouble throw push-push switch of the original invention and providelonger life for its springs, and to provide sealing means for said snapmechanism when it is used in a valve. During pretravel times, the valvewill stay closed or open, when opening the valve or closing itrespectively.

FIG. 1 depicts a sectional view of hereby improved electrical switchwith closed contacts.

FIG. 2 depicts a sectional view of same switch with open contacts. Bothsaid views are in relaxed positions.

FIG. 3 is a section along lines 3-3 of FIG. 7.

vFIG. 4 is a section view along lines 4-4 of FIG. 7-7.

FIG. 5 depicts the switch of FIG. I just before it snaps from close toopen position (FIG. 1 into FIG. 2).

FIG. 7 depicts the said switch just after it snapped from close to open;in other words, it is the subsequent position to that demonstrated inFIG. 5.

FIG. 6 depicts the switch in open position, subjected to aforcedepressing the cup which eventually will cause the switch to snap intothe closed-circuit posi- FIG. 8 depicts this switch in a positionsubsequent to FIG. 6 when it is ready to snap into close-circuitposition.

FIG. 9 depicts the use of this innovated snap mechanism in a valve inthe open circuit position.

FIG. 10 depicts this snap mechanism in a valve in the close-circuitposition.

FIGS. 11 and I2 and I3 depict the valve in transition from open to closeposition demonstrating the flexing of the lips.

FIG. 14 depicts this snap mechanism in a valve just before snapping fromopen to close position.

F I68. 17, I5 and I6 depict the valve in transition position from closeto open illustrating the flexing of lips and sealing of the ports'duringpretravel.

FIG. 17 depicts'this snap mechanism in a valve just before snappingfrom-close to open position.

FIG. 18 depicts a modified design of the loop spring switch in areleased position.

FIG. 19 depicts said switch of FIG. 18 in a pre-snap position. 1

FIG. 20 depicts said switch of FIG. 18 in actuated position after snap.All views are shown in sections.

FIG. 21 depicts the switch of FIG. 18 along lines 2I-2I.

In FIGS. 1-8, the improvement in this switch over that claimed in theoriginal application filed on Apr. I8, I969, consists of slits(undercuts) I13 and 105 in conical cup shape I03; and recesses I21 and102 in cup 101. The above splits would facilitate continuous flexing ofI16 (bottom portion of conical shape) and prevent fatigue of material atjunction points 112 and 117. Recesses 102 and 104 guides the top ofconical shape I03 and junction 112 between walls or bottom of cup,respectively in such a way that cone 103 reaches cup 101 at one levelwhen snap mechanism snaps from position shown in FIG. I to that shown inFIG. 2 and same cone I03 reaches cup IOI at another level when themechanism snaps vice-vcrsa. In other words, in FIG. 1,

the bridge-contact 114 is bridging contacts 118 and 119. The conicalshape I03 intimately supports cup 101. Whenforce is applied to the cup101, it depresses the perimeter of the conical cup 103 down, causing thebottom 116 to pivot about the ring 106 and raise stem 110; bottom ofcone 116 becomes compressed and buckles because there is not enoughspace in cup-cover 101 for developed area of I 16, when 116 is in thehorizontal position (see FIGS. 5 and 7).

Therefore, I16 stores energy and as soon as stem I10 raises junctionline 117 above the level ofjunction line 112, the stored energy in II6snaps the stem 110 up, cutting the contact of bus I14, and also liftingup cup 101 (FIG. 2). Now the circuit between terminals 118 and 119 isopen and the switch is stable. However, the snap mechanism reverseditself.

During its motion, the cover 101 is guided by means of projections 109protruding from the body 120 into the slots 122 of the cover-cup 101.

In order to reverse the position of the switch back to closed contact asit was inFIG. I, the cup-cover 101 would be depressed in the same manneras in aforeexplained case. However, at this time, stem 110 would (FIG.2) be depressed rather than cone 103. This would cause the bottom 116 ofthe cone 103 to pivot as well (FIG. 6). Then the horizontal projectionof bottom 116 increases as the angle between the horizontal axis andbottom of cone I16 decreases. This causes the walls of cone 103 tointerfere with high points 104 of cup-cover I01. Subsequently, saidup-right walls fold at the thinned section and junction 112 moves intorecess I21. Bottom 116 of cone 101 is also buckling (FIG. 6), storingenergy. Further, the cover-cup 101, continues to depress item 110, soedge of up-right circumference of the cone 103 slips into recess 102(FIG. 8). Further depression of cup-cover I01 causes folding andbuckling of cone 103 due to the geometrical curve of recess I02.Simultaneously, stem continues its pretravel toward the downward snap(see FIG. 17). By that time, junction point I I7 is lower from thejunction points 112; in other words, the snap mechanism crossed thecenter. Now, should the force on the switch be released, the conicalshape I03 willsnap into a relaxed position such as in FIG. 1, closingthe contacts 118 and 119; it would snap because of the built-up energyin elastic deformation of cone 103. It cannot snap back into position ofFIG. 2, because forthat the junction line 117 would have to pass backthrough the plane in which junction line 112 is located. In that planetakes place maximum compression of diaphragm 116. Since after theactuating force is released, the cone 103 will snap only in suchdirection in which it will progressively relax, it will snap intoposition of FIG. 1. Note that until it snapped, the contact 114 did notreach contacts 118 and 119. In other words, the make of circuit takesplace only after snap, and so is the break" of the circuit.

The travel of the cup-cover is limited by the upper limit 107 of theslot 122; when limit 107 reaches projection 109, the cup-cover I01cannot move downward any more, thus preventing undesirable reverse ofthe through of the switch. 123 is a hole in cup 101 for cir-.

culation of air in order to prevent vacuum within the cup-cover I01. I24is a projection from cup-cover 101; it makes the recess I02 deeper whichso delays the contact of cup 101 with cone I03, while the projection 124is maintaining intimate contact with stem I10.

FIGS. 9 to 17 illustrates the use of this innovated and improved snapmechanism in a valve. The valve has innovated seals such to keep thevalve in the same functional position relative to the circuit (open orclose) while pretravel and over-travel of the snap mechanism. Itconsists of several flexible lips molded integrally with the spool. Thelips take up one position relative to the' of open position. In FIG. 10,lip 137 seals the ports 132 and 139 and so cuts off the flow.

In FIG. 9, the lip 135 is sealing off the bottom portion of the bodypreventing fluid spillage. O-ring 141 is sealing off the upper portionof the body. Lips 136 and 137 are inactive in this position.

In FIGS. 11, 12 and 13 and 14 this valve is shown in transition from itsopen to closed position. As the spool 130 is raising (in the same manneras stem 110 aforeexplained), the lip 135 gets caught in groove 133 whilethe spool 130 continues to rise and, therefore, lip 135 becomes invertedas shown in FIG. 12. As the spool 130 moves up, the lip 135 ceases toseal bottom portion of the body; however, simultaneously, lip 136 movesup from recess area 142, folds over the shank 140 and seals the gapbetween the shank 140 and walls of the body 143. Gradually, the flowpassage is transferring itself from the top of lip 135 to underneath oflip 135. Note that the flow is not interrupted, since at some point, theflow passage is in both above and underneath the skirt 135, because lip135 is narrower than groove 133.

In FIG. 14, the pre-snap position, the lip 135 almost moved out of thegroove 133, and lips 136 and 137 are ready to move and seal the ports132 and 139 and the groove 133, which causes the valve to actuate intothe closed position as shown in FIG. 10. FIGS. 15 to 17 depict thevarious transition positions of this valve from closed to open of saidports 132, 139. In order to switch this valve into the open position,meaning from FIG. 10 into FIG. 9, the cup cover 101 is depressed also asexplained before. Then the spool pulls down junction line 144 of the lip137 by which the lip 137 is joined to the spool 130, while the free edgeof lip 137 is caught by ring 134.

FIG. 15 illustrates the inverting of lip 137 which enables to keep thevalve closed, the time of pretravel. Depression of cover 101 causesdepression of spool 130; however, lip 137 is caught by ring 134 andtherefore it starts to fold and invert as the spool 130 continues topull down. FIGS. 15 and 16 are sectional views of the valve with thelips illustrating the consecutive positions of the lips and theirinversion, until the valve snaps open.

Lip 136 caught by lip 137 in the groove 133, undergoes same process ofinversion as previously lip 137 in FIGS. 11 and 12. Note that lip 137gradually ceases to seal the ports 132 and 139 and groove I33 and it isreplaced by lip 136, then by lip 135.

In FIG. 17 is illustrated the pre-snap position of this valve into theopen position. Lips and 136 are scalers in this position. The other lip137 has slipped down below the groove 133. Then the valve spool 130 willsnap down; however, the lip 133 will be interfered with ring 134, andtherefore will be reversed into the position shown in FIG. 9.

In FIGS. 18-20 depict a modified design of the switch with a loop springclaimed in the original application filed Apr. 18, I969. Thismodification is intended to improve the snap action of this switch. Inthis improved version of the invention, the spring-loop 156 isprecompressed in assembly of the switch between projections of the body157 and 158 which are sloped toward the bottom of the switch. Both sidesof the generally rectangular loop spring are also inclined inwardly andare wedging against the sloped projections. So when the spring 156 isfurther depressed through actuations of the plunger 152, the springbecomes further compressed between projections 157 and 158 which meansthat the curves 167 and 168 become more compressed; therefore, arms 159and 160 closing in more toward the center causing curves 172 and 171also to compress more, as well as semi-loops and 166. The arms 162 and163 pivot about projections 169 and respectively lifting semiloop 164 tothe axis, thus causing curves 179 and 180 to compress (see FIG. 19) ansso is semi-loop 173. Consequently, semi-loops 164 and 165 and 166 andcurves 167, 168, 179, 180 all become stressed and relatively a bigamount of energy would be stored in so much material (approximately 10times more than in conventional switches of the same size). When arms162 and 163 go over center, the spring loop 156 would snap into positionshown in FIG. 20. In this position, movable'contact 173 on semi-loop 164is cut off from stationary contact 172. The moving contact 174 isengaged with stationary contact 176. Semi-loop 166 is just sliding alongcontact area 175 which is a common terminal. In this position, some ofthe constrained areas are released. However, since most of the abovesaid semi-loops and curves are constrained, the switch will snap back assoon as the plunger is released. Note that all contacts in this newswitch are sliding. During pretravel, the moving contact 173 and 174 aresliding along stationary contacts 172 and 176 respectively. Also, thiscauses the moving contacts to clean the stationary contacts twice eachcycle.

153 and 154 are the stationary alternate terminals. 155 is the commonstationary terminal. The body of this switch consists of two pieces 151and 161. (See FIG. 21). Part 161 is L-shaped. This facilitiates theassembly of this switch. The assembly would be as follows: The Base 1would be dropped into a cage into a 45 percent position with thevertical axis; then the stationary contacts 153, I54 and 155 would beforced in (or they could be molded in as inserts); then, the loop spring156 would be dropped in freely. Then plunger 152 would be dropped in topof loop spring 156; then glue would be applied to the L-shaped 161 andit would be dropped in the reverse position also under 45 on top ofplunger 152 and body 151. Then pressure would be applied to reversedL-shape 161 at two sides 90 apart. The chamfers on 151 and 161 willguide the pieces together. 161 will push the plunger 152; in turn, theplunger will set the spring 156 between projections 157 and 158prestressing in it the predetermined amount. This will eliminate humanerror and experience presently necessary for prestressing springs insnap switches.

I claim:

1. A valve comprising a body with a longitudinal bore,-acircumferentially extending groove in the bore by the wall of the grooveso that the outer portion of 5 the lip trails the direction of movementof the stem thereby sealing the stem with the bore, and means betweenthe stem and the body to reciprocate the stem therein.

2. A valve as in claim 1 including means spaced from the groove sealingthe stem with the bore.

3. A valve as in claim 1 including a plurality of spaced flexiblelipmeans, each adapted to be flexed by the wall of the groove as the lipmeans passes thereby.

4. A valve as in claim 1 including snap action means between the bodyand the stem to reciprocate the stem and means to limit travel of saidstem in each direction.

5. A snap mechanism with one biased position comprising a body, aresilient spring-loop of generally rectangular shape a plunger-actuatorextending into said body and resting against top of said spring-loop,two spaced projections extending into said body from one said andengaging bottom portion of said spring-loop, two opposite ends of saidspring-loop wedging against two sloped projections extending into saidbody from opposite end walls, whereby movement of said plungeractuatortoward said projections cams two spaced ends of said spring-loop towardeach other and causes said loop to compress and two sides of said bottomportion of said spring-loop to pivot about said two projectionsextending into said body from one side lifting toward the top the centerportion of bottom of said springloop.

6. A snap mechanism as defined in claim*5 whereas said opposite ends ofsaid spring-loop extending downwardly from said top portion of saidspring-loop are sloping down toward each other.

7. A snap mechanism as defined in claim 5 whereas said body comprises anintegrally molded L-shaped piece with a cut out for the actuator,whereby said L- shaped piece simultaneously covers two sides of saidmechanism.

8. A snap mechanism comprising a stem, a cup having an outer wallextending substantially parallel to the stem, a conical bottomconnecting the wall to the stem, the connections adjacent said wall andsaid stem being of reduced thickness as compared to thickness of thebottom, whereby said bottom can be snapped over center from concave toconvex and vice versa, whereby said connections and said bottom arecompressed as the bottom goes over center.

9. A device as in claim 8 where said connection between the wall and thebottom is substantially entirely compressed by the wall portion.

10. A device as in claim 8 where the connection between said wall andsaid bottom is short so that the thicker portion of said bottom bearsagainst said wall as said bottom goes over center.

11. An operator comprising a body portion, a pivot ring extending fromone end of the body spaced from the outer edge of the body, atelescoping cover slidably attached to the body, an annular projectionon the inner wall of the cover outwardly of the ring and within theouter edge of the body, a concave-convex spring member floatably placedbetween the ring and the cover, the spring member bearing on theprojection.

12. A device in claim 11 wherein at least one recess is provided withinthe end of the cover opposite to the ring.

1. A valve comprising a body with a longitudinal bore, acircumferentially extending groove in the bore mediate the ends of thebore, at least two ports in the body connected with the groove, a stemreciprocal in the bore, at least one flexible lip means on the stemadapted to engage the wall of the bore and to be flexed by the wall ofthe groove so that the outer portion of the lip trails the direction ofmovement of the stem thereby sealing the stem with the bore, and meansbetween the stem and the body to reciprocate the stem therein.
 2. Avalve as in claim 1 including means spaced from the groove sealing thestem with the bore.
 3. A valve as in claim 1 including a plurality ofspaced flexible lip means, each adapted to be flexed by the wall of thegroove as the lip means passes thereby.
 4. A valve as in claim 1including snap action means between the body and the stem to reciprocatethe stem and means to limit travel of said stem in each direction.
 5. Asnap mechanism with one biased position comprising a body, a resilientspring-loop of generally rectangular shape a plunger-actuator extendinginto said body and resting against top of said spring-loop, two spacedprojections eXtending into said body from one said and engaging bottomportion of said spring-loop, two opposite ends of said spring-loopwedging against two sloped projections extending into said body fromopposite end walls, whereby movement of said plunger-actuator towardsaid projections cams two spaced ends of said spring-loop toward eachother and causes said loop to compress and two sides of said bottomportion of said spring-loop to pivot about said two projectionsextending into said body from one side lifting toward the top the centerportion of bottom of said spring-loop.
 6. A snap mechanism as defined inclaim 5 whereas said opposite ends of said spring-loop extendingdownwardly from said top portion of said spring-loop are sloping downtoward each other.
 7. A snap mechanism as defined in claim 5 whereassaid body comprises an integrally molded L-shaped piece with a cut outfor the actuator, whereby said L-shaped piece simultaneously covers twosides of said mechanism.
 8. A snap mechanism comprising a stem, a cuphaving an outer wall extending substantially parallel to the stem, aconical bottom connecting the wall to the stem, the connections adjacentsaid wall and said stem being of reduced thickness as compared tothickness of the bottom, whereby said bottom can be snapped over centerfrom concave to convex and vice versa, whereby said connections and saidbottom are compressed as the bottom goes over center.
 9. A device as inclaim 8 where said connection between the wall and the bottom issubstantially entirely compressed by the wall portion.
 10. A device asin claim 8 where the connection between said wall and said bottom isshort so that the thicker portion of said bottom bears against said wallas said bottom goes over center.
 11. An operator comprising a bodyportion, a pivot ring extending from one end of the body spaced from theouter edge of the body, a telescoping cover slidably attached to thebody, an annular projection on the inner wall of the cover outwardly ofthe ring and within the outer edge of the body, a concave-convex springmember floatably placed between the ring and the cover, the springmember bearing on the projection.
 12. A device in claim 11 wherein atleast one recess is provided within the end of the cover opposite to thering.